We’re all supposed to eat more leafy greens, right? And bagged lettuce makes that oh, so convenient, right? Yes, but… Bagged and pre-washed lettuce, as well as other bagged produce, can present health dangers. Not just harmful bacteria that can lurk on leaves, but chemical washes used to clean bagged lettuce can cause extreme stomach upset. It’s just another reason to skip the bagged lettuce altogether.

There is no denying that bagged lettuce is easy and quick. And if you’re a busy mom trying to get dinner on the table and time is at a premium, bagged lettuce seems like a good solution. But before you pick up that bag, there are 5 things you should know about bagged lettuce.

1. While there is some contamination risk associated with eating ANY produce, bagged lettuce increases your risk exponentially. Why? Because bacteria adheres more easily to the surface of greens once it has been cut. That means that using pre-cut lettuce exposes you to more bacteria.

2. Don’t expect that the bag of lettuce you buy all came from the same plant —or even the same farm. The process of washing, chopping and bagging lettuce is done by machine. Heads of lettuce are collected from many different sources, and then put through the process together. This means that there is a greater chance of cross-contamination.

3. The chemicals used to wash and clean the lettuce can make you sick, just like bacteria can. Many companies use a mixture of chlorine and water to disinfect the lettuce during the washing process. Chlorine is indigestible, and can cause severe stomach upset, as well as reactions ranging from mild cramping to diarrhea and hospitalization. Recently, some companies have started to use a chemical compound called FreshRinse. which contains organic acids, including lactic acid (found in milk) and peracetic acid. Many people have proved sensitive to these compounds, too.

4. Washing, decontaminating and bagging lettuce takes a lot of resources. From extra water for the now-normal practice of triple-washing, to the creation of plastic bags in which to store the produce, all of this is less than eco-friendly.

5. The lettuce your eating has probably been bagged for at least two weeks prior to getting to your store. By the time the lettuce is collected, processed, bagged and shipped, it’s likely been 2 weeks. Then it may sit in a holding facility for a while before being brought to the retail floor. So when you see the sell-by date is still 2 weeks out, remember how long that lettuce may have been sitting in the bag already.

So the bottom line is that you are better off preparing your own lettuce. Let’s face it, it takes only a few minutes to wash and chop lettuce.Doing it yourself will definitely save you some coin, and might even save you a trip to the doctor or emergency room.